[Utah_jeepster]

actually its weight to torque ratio.
The lighter short wheel based Jeeps dont need such a massive engine to move it on and off road.
The "I" configuration produces massive amounts of torque at lower RPM's compared to a "V" configuration.
For a "V" motor to produce the same amount of torque you need to lengthen the stroke but reduce the compression ratio to a 10-1. The Scout 345 as an example.
The "V" configuration was designed to produce lots of torque at higher RPM's, the only problem was weight and fuel comsuption. For a good example look at the muscle cars of the 60's and early 70's.
Alot of top end speed but very little low end toque unless the motor was modified and the chassi re-geared for the 1/4 mile strip racing.
With a jeep you dont need nor want high RPM torque. But straight low end grunting power.
The "I" configuration has been around longer than the "V" design.
With the ability to save on casting weight, less moving parts,bearing seats for the cam and crank and space saving of the "I" configuration has made the straight 4 and 6 motor a Jeep trade mark for the amount of torque they produce.
A proven motor design that has lasted for over 85 years( the first cars were an inline 4). And will last another 20-30 more till the 4 pack ( "V-4") hybird motors will dominate automotive industry